| module PredictionIO |
| |
| # This class handles multithreading and asynchronous requests transparently for the REST client. |
| class Connection |
| |
| # Number of pending asynchronous request and response packages. |
| attr_reader :packages |
| |
| # Number of connections active |
| attr_reader :connections |
| |
| # Timeout in seconds |
| attr_reader :timeout |
| |
| # Spawns a number of threads with persistent HTTP connection to the specified URI. |
| # Sets a default timeout of 5 seconds. |
| def initialize(uri, threads = 1, timeout = 5) |
| @packages = Queue.new |
| @counter_lock = Mutex.new |
| @connections = 0 |
| @timeout = timeout |
| threads.times do |
| Thread.new do |
| begin |
| Net::HTTP.start(uri.host, uri.port, |
| :use_ssl => uri.scheme == 'https') do |http| |
| @counter_lock.synchronize do |
| @connections += 1 |
| end |
| catch(:exit) do |
| http.read_timeout = @timeout |
| loop do |
| package = @packages.pop |
| request = package[:request] |
| response = package[:response] |
| case package[:method] |
| when "get" |
| http_req = Net::HTTP::Get.new("#{uri.path}#{request.qpath}") |
| begin |
| response.set(http.request(http_req)) |
| rescue Exception => details |
| response.set(details) |
| end |
| when "post" |
| http_req = Net::HTTP::Post.new("#{uri.path}#{request.path}") |
| http_req.set_form_data(request.params) |
| begin |
| response.set(http.request(http_req)) |
| rescue Exception => details |
| response.set(details) |
| end |
| when "delete" |
| http_req = Net::HTTP::Delete.new("#{uri.path}#{request.qpath}") |
| begin |
| response.set(http.request(http_req)) |
| rescue Exception => details |
| response.set(details) |
| end |
| when "exit" |
| @counter_lock.synchronize do |
| @connections -= 1 |
| end |
| throw :exit |
| end |
| end |
| end |
| end |
| rescue Exception => detail |
| @counter_lock.synchronize do |
| if @connections == 0 then |
| # Use non-blocking pop to avoid dead-locking the current |
| # thread when there is no request, and give it a chance to re-connect. |
| begin |
| package = @packages.pop(true) |
| response = package[:response] |
| response.set(detail) |
| rescue Exception |
| end |
| end |
| end |
| sleep(1) |
| retry |
| end |
| end |
| end |
| end |
| |
| # Create an asynchronous request and response package, put it in the pending queue, and return the response object. |
| def request(method, request) |
| response = AsyncResponse.new(request) |
| @packages.push(:method => method, |
| :request => request, |
| :response => response) |
| response |
| end |
| |
| # Shortcut to create an asynchronous GET request with the response object returned. |
| def aget(areq) |
| request("get", areq) |
| end |
| |
| # Shortcut to create an asynchronous POST request with the response object returned. |
| def apost(areq) |
| request("post", areq) |
| end |
| |
| # Shortcut to create an asynchronous DELETE request with the response object returned. |
| def adelete(areq) |
| request("delete", areq) |
| end |
| end |
| end |